Field:
The present disclosure relates to a wavelength converting member containing a fluorescent material that is configured to emit light, upon receiving an incident light, of a wavelength different from the wavelength of the incident light, and to a light source device having the wavelength converting member.
Description of the Related Art:
In recent years, light source devices employing light sources that use semiconductor lasers (LDs) or light emitting diodes (LEDs), and fluorescent materials configured to emit light, upon receiving an incident light, of a wavelength different from the wavelength of the incident light, have become popular. In such light source devices employing fluorescent materials, an increase in the temperature of the fluorescent materials while converting wavelength may result in a decrease in the light converting efficiency of the fluorescent materials. To address such a disadvantage, JP2010-197500A proposes a light source device in which a coolant containing a fluorescent material is circulated in a circulation channel by a pump while the coolant containing the fluorescent material is cooled by a cooler provided to the circulation channel.
The light source device described in Japanese unexamined patent publication No. 2010-197500 requires a circulation channel and a pump to circulate a coolant in the circulation channel, so that miniaturization of the light source device is difficult, and the number of components also increases, which increases the manufacturing cost. In particular, driving a pump increases the energy consumption in operation.
Accordingly, an object of the present disclosure is to improve disadvantages described above, and to provide a wavelength converting member that can cool the fluorescent material efficiently without using a driving source and exhibits low energy consumption in operation, and to provide a light source device having the wavelength converting member.